Key facts
- Even mild dehydration can reduce strength and endurance.
- Needs rise with sweat, heat, and training volume.
- Electrolytes like sodium support fluid balance.
- Thirst and urine colour are simple practical guides.
Water is involved in nearly every process in the body, from transporting nutrients to regulating temperature. During exercise you lose fluid through sweat, and even mild dehydration (1–2% of bodyweight) can measurably reduce strength, endurance, and focus, making hydration a genuine performance factor.
There's no single magic number — needs depend on body size, climate, and how much you sweat. Pale-yellow urine and responding to thirst are practical guides for most people. Around hard or long training, replacing both fluid and electrolytes (especially sodium) helps maintain balance and performance.
Frequently asked questions
How much water should I drink a day?
It varies with size, climate, and activity. Rather than a fixed number, use thirst and pale-yellow urine as guides, and drink more around training and in the heat.
Do I need electrolytes or just water?
For everyday activity, water is usually enough. During long, sweaty, or intense sessions, adding electrolytes — especially sodium — helps maintain fluid balance and performance.
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